ADHD in 5 year old? *UPDATE*

So over the last year, my daughter has had major behavioral changes. At first we thought it was because of our new baby but things have gotten so bad. I understand how she must feel having a new sibling but over the past few months she has changed and I am not sure if it is normal. She has been

- interrupting

-trouble taking turns/ sharing

-will scream(bloody murder)/cry if she doesn't want to wear a certain outfit or doesn't want to go somewhere/ do something

-problems staying quiet

-trouble paying attention when we talk to her

-will not clean her room/ clean up after herself

-has not wanted to brush teeth/ take a bath

- Will scream bloody murder if asked to clean

I know a lot of this seems normal but the thing is really her emotions. She will break down at random times. She will hit us, yell at us.

Her screams are horrible, I always feel like someone will call the cops because they are that loud. Idk what to do. She was not like this before. Advice?

I tried so many things but I am thinking it might be more..

How would I go about discussing this with her doctor?

Would I need a referral for a mental health specialist or would I be able to contact them myself?

* made an appointment with a therapist. After an evaluation, she gave me some papers for myself and my daughters teacher. The papers are the Vanderbilt ADHD diagnostic rating scale. From the rating I gave her, it seemed like ADHD was possible, after seeing the paper her teacher filled out, it seems like this is most likely ADHD. Obviously I cannot say for sure, but most of the results were positive. I didn't realize she was having so many problems at school. She is a good girl and I think her teacher probably assumed this behavior was due to the baby. After I talked to her, she said she did notice some signs. We will find out in 10 days. Thanks for your advice!